imported python module of functions does not recognise package imports

Question

I have files in a repo with the following Structure:

RepoName\main.py

RepoName\functions\myfunction.py

Inside myfunction.py is:

import pandas as pd
def make_ticker_list():
    constituents = pd.read_csv("myfile.csv")
    
    ticker_list = ""
    for x in constituents:
        ticker_list = ticker_list + x + " "
    del x
    return ticker_list

and inside main.py is:

import pandas as pd
from functions.myfunction import *

new_list = make_ticker_list()

but when I run main.py, I get:

NameError: name 'pd' is not defined

I've imported the pandas alias already in main.py so I don't know why I get this error. I added it to myfunction.py as shown above, but that also didn't work

Tried so far and didn't work:

1. Adding import pandas as pd into the myfunction.py file, as shown above
2. Adding a '__init__.py' into the functions folder

The logic makes sense because when I load another toy function into myfunction.py, eg:

def toy()
    return 2

And I run toy() in main.py, it works fine

Any ideas what the problem might be?